Photo caption: "Two dodecahedra and an icosahedron on display in the Rheinisches Landesmuseum Bonn, Germany."
A Roman dodecahedron or Gallo-Roman dodecahedron is a small hollow object made of copper alloy which has been cast into a regular dodecahedral shape: twelve flat pentagonal faces, each face having a circular hole of varying diameter in the middle, the holes connecting to the hollow center. Roman dodecahedra date from the 2nd to 4th centuries AD and their purpose remains unknown. They rarely show signs of wear, and do not have any inscribed numbers or letters.
They were found in coastal Southeast Asia, but not in India/China/MENA
my inductive theory is that this was a very specific niche market borne from a Southeast Asian merchant who saw these in Europe and adopted the idea to sell them as trinkets back in SEA. The fact that they were never found anywhere else means nobody really thought about selling them. In fact there might have even been a stigma against selling them, if they were used as a test of skill, basically buying your skill instead of earning it.
The SEA ones are also often made of gold, while the European ones are made of bronze. The Europeans who had them valued them, because they were found among coins, but they were usually made of cheaper metal like bronze, which IMO strengthens the "test of skill" argument
Gold is an easier metal to work with than bronze I believe, to add to your theory
true, but I think they wanted gold because it looked pretty